Water purifier



D. H. QUINN WATER PURIFIER Fned'Feb. 25, 194,4,

Jan. 27, 1948,

E mvENTo BYDAWD H. @umm Patented Jan. 27, 1948 UNITED STATES PATENT QFFICE WATER PURIFIER David H. Quinn, United States 'Navy Application February 25, 1944, Serial No. 523,843

18 Claims. (Cl. 2104-112) (Granted under the act of March v3, 1883, as 'amended April 30, 192g; 370 0. G. 757)'.

This invention relates to water purifying equipment, and in particular to such equipment as will provide water for drinking purposesyfrom water which would otherwise `be unfit to drink because of pollution.

The provision of pure drinking water is always a factor which must be considered during military operations. Troops in the eld are often separated from their source of supply of pure drinking water. The small amount of Water that each man can carry in his canteen is not suiicient to last him for more than a short time. When this has been used, the men are sorely tempted to drink water from any source even though they know that it is contaminated. Normally, such contaminated water is fairly abundant.' and in order to assuage their thirst the men will drink it even against their better judgment. Almost invariably they will become ill and unfit for duty, I

and some fatalities result.

The purifying equipment which is the subject of this invention is particularly adaptable to be constructed of small size so that it can be carried by an individual as an article of equipment. A model approximately seven and one-half inches long and two and one-fourth inches in diameter, which weighs approximately one pound complete, has beenfound to remove 100% of the bacteria, turbidity, odor and taste from a samp`e of highly polluted water. This small model .purified more than ve gallons of Water before a cleaning operation was necessary. The unit is designed to be easily dismantled for cleaningwhich operation' takes approximately iive minutes. Due to its small size and light weight, the purity of its efiiuent, and ease of cleaning, the unit ca'n be easily carried by a soldier in combat or patrol operations, and he will always have with him means for supplying himself with pure drinking water. While the equipment forming the subject of the present invention was designed primarily to fulll the need of troops it is to be understood that it is equally useful to campers and the like, and that the dimensions given above arenot limiting but by way of example. Larger units, havingl greater capacity and a longer life fl.' between cleaning operations are within the scope oi the invention.

. It is the primary object of my invention to provide an improved portable water purifying equipment which is capable of complete puricomprising two treating units, one of which is immersed in the body of water from which the supply is drawn, and the other of which is a unit from which the puried water is dischargedunder pressure, there being a pump to suck water through the immersed unit and force it through the second or discharge unit. When not in use the two units are screwed together to conserve space and to make an easily carried unit of equipment.

Other objects will become apparentes the de scription proceeds in connection with the annexed drawings, in which:

Fig. 1 is a sectional view in side elevation of the complete equipment, the section shown being in a vertical plane passing through the longitudinal axis thereof Fig. 2 is a partial plan view of the equipment substantially along the line 2 2 of Fig. 1 butshowing the ilexibleoutlet hose coiled, and with its connection in its true relationship with respect to the top of the unit rather .than as shown in Fig. 1 where it is slightly rotated and displaced rfor purpose of illustration.

Fig. 3 is a partial sectional view of the handle, taken along the line 3--3 of Fig. 1, and looking in the direction of the arrows;

Fig. 4 z's a sectional view similar to Fig. 3 of a modied handle, but taken on a plane passing ccmplete'y through the handle instead of only to the axis of the pump shaft as is Fig. 3;

Fig. 5 is' a sectional view along the line 5--5 of Fig. 1 on line 5-5 of Fig. 8 and looking in the direction of the arrows.

Fig. 6 is a partial plan view of the central drainage member and support shown in section in Fig. 1.

Fig. 7 is a considerably enlarged view, of a portion of the right end of the central drainage member and support shown in section in Fig. 1.

Fig. 8 is a frontrelevation of the lower portion of -the main ltering unit shown" in section in Fig. 1. f

As shown in-Fig, 1 the assembly comprises a main lilter' unit I and a pre-filter unit 2 connected Iby a length of flexible conduit or hose 3. During filtering operations, the water is drawn through the illters in unit 2 by pulling upon a pump shaft 4 in the main filter unit l The water passes from-the pre-filter 2 through the hose 3 and into a pump cylinder 5. The water is retained in the. barrel 5 by a one way check valve 6 until the pump shaft 4 is given a down stroke whereupon the water passes through anotherfcheck valve 1 to thelters in the main apparatus is not in use, however. the pre-lter unit is attached to and carried by the main iilter unit, as will be described later.

The pre-filter unit 3 comprises a cylindrical housing I having internal threaded portions il and I2 respectively at each end. 'lhe portion It is longer than the portion I2 for a purpose to be described. A pair of periorated disc shaped supports i3 and I4 are threaded into the portions II and I2 and clamp between them a pair of assembled iilter units winch are separated by a common disc shaped drainage member and support I5. Each iilter unit comprises a pair of ring like spacers I6 and I1 which are clamped between the support and drainage member l and each perforated support i3 and lo, thus providing spaces I8 and IS respectively which are lled with very fine loose illtering material, such as diatomaceous earth.

In order to conne the line material in the spaces' I8 and I9, very line mesh metal screens or porous supports or the like 2B, 2i, 22, and 23 are clamped between spacer I5 and supports l3'and I5, and between spacer l1 and supports i4 and I5. By way of example, the screens 2li- 23 mal1 be of 325 mesh "Monel metal when the ne material confined therebetween is diatomaceous earth. The drainage member I5 separates and keeps the two interior screens 2i and 22 from collapsing against each other from the pressure, and also provides a drainage or eiiluent channel leading to a discharge tting 24 to which the hose 3 is attached. As shown in Fig. 1 and Fig. 7 the drainage and support member I5 has ridges or projections on each side which support the screens 2 I and 22. One or more internal passageways .25 communicate with an annular groove 21 on the periphery of the support, the groove 21 being in communication with a passageway 23 which is connected to the discharge tting 24. The water which passes through screens 2I and 22 into the valleys between the projections 25 passes into the passageways 26 and the annular groove 21 by means of passages 29 leading from each such valley.

The outside surfaces of the perforated supports I3 and I4 are substantially fiat, but their interior surfaces are provided with concentric annular ridges which support the screens 20 and 23 as during backwashing. The valleys between the ridges communicate with the outside of the unit or housing through holes 30 passing through the supports I3 and I4, there being at least one hole for each such valley.

The hose 3 is slipped over an inlet tting 3| in a base portion 32 of the main lter unit I.

The base portion 32 is shown to be integral with the pump cylinder 5, but they may be made separately and locked in ilxed relationship. An exterior tubular casing 33 is threaded into the base 32 and sealed by a gasket 34. The upper end of casing 33 is seated against a gasket 35 in annular groove of a lower head member 36.

The head 35 has a sliding t over the pump cylinder 5. A'n upper head member 31 is attached to the top of the lower head 36 by means of matpump cylinder 5, nts into the groove containing gasket 40. When the 'gland nut 4I is screwed.

. down on the threads 42 on the pump cylinder 5 it compresses the head elements 3d and 31 against the top of the casing 33. which is itself threaded to the base 32. If desired, the casing 33 may be only seated against the base 32 as it is seated against the head 35, in which case the seal at gasket 34 will be due to the pressure of gland nut 4|-, The gaskets 35. 39 and 43 provide sealing means as will be understood. The gland nut 4l,thus holds the casing 33. base 32 and the upper and lower head members 3l and 36 of the main lter unit i in assembled relationship.

As shown in Fig. 1 the base 32 has a. tapered bore 43 in axial alignment with the bore of the pump cylinder 5. Seated in the bore 43 is a valve 44 having a mating tapered portion 45. At the bottom of the tapered portion 45 the valve 44 has an annular ilange 45 having a tapered underside. As shown in Figs. 5 and 1, a U-shaped retainer pin 41 which slides in parallel holes 48 and 43 in the base 32 and aligned with the tapered underside of flange, slips under flange 46 and resiliently urges and retains the valve 44 in the tapered bore 43. The resilience of this force is due to the fact that the retainer pin 4T is of spring material. The annular iiange 46 lies within an annular recess 50 in the base 32, and

as shown in Figs. 5 and 1 the walls of this recess do not permit the legs of the retainer pin 41 to be spread out suiliciently to slip out from under the ange 46. A recess 41a is provided in the base so that the portion connecting the legs of the pinv 41 is accessible for removal of the pin from the base.

The valve 44 terminates in a base having substantially the same outside diameter as the base 32. As-shown in Fig. l the base of valve 44 has an upper annular shoulder 44a seating within a mating internal shoulder in the bottom of the base 32.' The base of valve 44 further has external threads 5i which mate with the internal threaded portion i I of the pre-iilter unit 2. A second U-shaped pin 52 has its two legs passing through parallel holes in the base of valve 44. When the pin 52 is pushed completely into the holes, its connecting portion which joins the two legs is seated in a recess 52a below the roots of the threads 5I, so that it willl not interfere with threading the pre-filter unit onto the threads 5i when the equipment is not in use, the recess being large enough to allow the connecting portion to be engaged by a tool `or nger. The holes in which the legs of the pin 52 slide have portions of small and larger diameter and the ends of the legs'are split or upset to keep pin 52 frombeing pulled entirely out,lin a similar' manneras the wire extensible handles of Fig. 4 are mounted, as will be described later in connection with Fig. 4. The U-shaped pin 52 has a dual purpose when it is pulled out of its recess so that it projects from the side of the base of valve 44. The rst and primary purpose is to provide a handle with which to rotate the valve 44 fora purpose to be described. The secondary purpose is to provide a foot rest to hold the main filter unit I in place on the ground when operating the pump to lter water.

I'he valve 44 has within it the ball check valves 6 and 1, both of which are spring pressed into closed position as shown in Fig. 1. Valve 6 permits one way flow into the pump cylinder by way ofthe passage 53 in valve 44. Valve 1 permits one way ow out of the pump cylinder 5 by way of the passage 54 in valve 44. These passages 53 and 54 pass through the side walls of the tapered portion 45 of valve 44 in the same plane. and 180 degrees apart. When in the position of Fig. 1, passage 53 communicates with an inlet passage 55 in the base 32 which connects with inlet fitting 3|. At the same time the passage 54 in the valve communicates with an outlet passage 56 which terminates in an annular channel 51 to distribute the water evenly aroundthe inside of the main filter unit. With the valve 44 in this position, when the pump shaft 4 is pulled up the pump cylinder will be filled with vwater which has passed throughthe pre-filter unit 2 and the check valve 6. On the down stroke of the pump the check valve 1 opens and permits the discharge of the water from the pump cylinder 5 into the main filter unit by way of outlet passage 56 and channel 51.

When it is desired to backwash the pre-filter unit the pump cylinder is first lled vwith water while the valve 44 is in the position of Fig. 1. The handle 52 is then pulled out and the valve 44 is rotated 180 degrees until passage 54 aligns with passage 55 and passage 53 aligns with passage 55. Then when the pump shaft 4 is pushed down, the Water in the cylinder 5 is discharged through valve 1, passage 55 and hose3 and backwards through the filtering. material in the prefilter unit 2 to backwash it. The pump cylinder 5 may be refilled for more backwashing-strokes by pulling the pump shaft up again while the interior of the casing 33 is vented to the atmosphere at the top as through the fitting 8 and Ahose 9. The filtering material, such as diatomaceous earth, used in the pre-filter unit will be slightly packed against the screens 2| and 22 during normal filtration, and will thus form a pre-coat upon the screens 2| and 22. will not be cracked and broken `by ordinary shocks as will those types of pre-coats which are built up on a support by mixing diatomaceous earth, for example, with the influent liquid so as to gradually build up on the support as filtration proceeds. In my device the pre-coat of diatomaceous earth is already built up on the support when filtration begins, since it is confined between two screens. Yet it is packed loosely enough between the screens so that backwashing will disturb and clean it, as well as any particles retained by the outer screens 20 and 23. A stop pin 58 mounted on the valve 44 moves in an arcuate slot 59 (Fig. 5) in the bottom of the base 32 and since the slot extends for only 180 degrees, the valve 44 is limited to a 180 degree movement, by which means the rissages 53-56 are properly lined up at the end of the rotative movements of valve 44. I y

An annular ring 60 has a central bore which slides over the pump cylinder 5. On its upper surface the ring 60 has a plurality of blind holes .or seats into which are cemented the lower ends of one or more annular rows ol? ceramic filtering tubes 6|.

'I'he lower head element 36 has similar -seats on its bottom surface in axial alignment with the' seats in the ring 80, the upper ends oi the filtering tubes 3| being seated and cemented therein. ,The central bores of the tubes 6| communicate with-an annular groove 62 on the upper side of the head'a by means of,holes 63 passing through the head.

A corresponding annular groove 54 in the underside of the upper head 31 overlies the annular groove 62. The eiiluent fitting 8 communicates with the groove 64. A screen 65 is soldered or otherwise fixed over the groove 54 to prevent the passage of particles of activated carbon or the like into the effluent fitting 8, the bores of the filtering tubes 8| being normally filled with activated carbon which has been silvered, as will be described later.

The vspace within the casing 33 and between the filtering tubes 5I is also normally filled with silvered activated carbon, there'. being a, filling hole. 56 passing through the base 32' and closed with a screw plug 61. In order to prevent the passage of carbon particles into the valve 44 from `the casing 33 a screen 68 is placed either in the passage 56 or over the annular channel 51.

the central'bore of the gland nut 4| having a sliding fit on the pump shaft 4, so that the washer assembly 59 which has a sliding fit in cylinder 5 will not permit the pump shaft 4 to be pulled out of the cylinder 5, The washer assembly 69 includes a central metal washer having a sliding fit within cylinder 5 and separating the opposed flexible cup washers which are pressed against the wall of the cylinder 5 by means of expanding internal spring washers 10.

' When the equipment is not in use 'the prelilter 2 will be attached to the main filter unit by means of the mating threads and 5| as described above. In order to get the flexible eiilu- This pre-coat, however,

.wire extensions on the handle 1 The end portions 1| are the ends of wire hanextension is made Vof one ent hose 9 out of the way it is coiled around the pump shaft and gland nuty as shown in Fig. 2. With the pump shaft in its down position l.the hose 9 is retained in its coiled position by means of the downwardly turned end portions 1| of the dle extensions shown more clearly in Fig. 3. Each piece of wire having its ends sliding in holes 13 and 14 in the handle 12. In the embodiment of Fig. 3 the holes 13 and 14 are slightly larger in diameter than the wire, which has projections 98 seating in internal recesses 99 in the bores 13 and 14. The projections engage in the recesses due tothe natural springv of the wire and will retain the wire handles -in either the closed position shown in' Fig. 3 and in the solid lines of Fig. 1, or in the extended .position indicated by the brokenlines in Fig, 1. With f the wire handles in the extended position a larger handle and-a better grip is available than when using only the solid handle 12.

In Fig. 4 another embodiment of the extendible wire handles is shown. In this case when they are in closed position the straight or leg portions extend substantially through the length of the necessary in this `em- 1 1 handle 12. Four holes are bodiment. Substantially one-half of each hole is the same diameter as the wire which has a sliding t therein. In each case this is that portion ofthe hole near the bent mid portion of the wire. The remaining portion of each hole. near the straight end portions of the wire, are of larger.

diameter. The ends of the wires are upset or spread so that they slide in the larger portions of the holes but are stopped when they reach the small diameters as the wire handles are pulled out. With this embodiment the wire extensions are stronger than those of Fig. 3 since even in extended position substantially half of their length still have abearing portion within the handle 2.

l on the eiiluent will be either oligodynamic or The top surface of the gland nut Il has a cirm cular row of projecting lugs best shown in Figs. 2 and 1. The lower surface of the handle 12 has a mating circular row'of projecting lugs 16 which fit between the lugs 15 when the handle 12 is at the bottom of its stroke. By means of these mating sets of lugs the handle 12 can be used as a wrench to tighten or loosen the gland nut 4|. When loosened, the gland nut can be entirely disengaged from the threads 42 on the top of pump cylinder 5. The entire assembly of filtering tubes 6| can then be removed from the case 33 by lifting the assembly comprising the upper head 31' and the lower head 3B from the top of vfirst, and then renserted into the casing through the filling hole G6 after been reassembled.

In order to facilitate the disassembly o f the upper head 31 from the lower head, the upper head is provided with means such as diametrically spaced lugs 11 and 18 which may beengaged by the main filter unit l has a wrench to loosen the upper head.

The pump shaft 4 is hollow to provide a storage space for one or more vials 19. A screw plug 80 closes the open upper end of the shaft to retain the vials therein. The vials contain chemicals which may be in pill orcapsule form 8|, and are thus readily available to make a cleaning 0r `oxidizing solution to clean the filter tubes as described. It is desirable that the pre-filter unit be treated with a cleaning or oxidizing agent from time to time. This is done by dissolving a suitable number of pills 8| in a vessel of water, Then the pre-iilter unit can be washed back and forth in the treated water, and some of the, water should be drawn through the pre-filter by-operating the pump The chemicals' should iinallv be washed out by pumping other water through the pre-filter, either in the normal direction or by backwashing. If the water should need chemical puriiication some of the pills carried in the vials may be of a type useful in the chemical purification of water.

In order to reduce the weight of the equipment and to make the filtering tubes 6| visible, the case 33 is advantageously made of atransparent plastic. When the filtering tubes are visible in this manner their condition -can be observed and it can more readily be determined whether or not they need cleaning.

The activated carbon used within and between the filtering tubes 6| is advantageously coated or treated with very ne particles of silver such as colloidal silver. Th.- action of this colloidal silver The tubes may also be adgermicidal and insures complete sterilization of the eilluent in addition to the deodorizing and degustating action of the activated carbon. The silver particles are so small as to be embedded or adsorbed in the pores of the activated carbon and will not normally be dislodged by the water flow through the carbon.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental i purposes without the payment of any royalties thereon or therefor.

I claim:

l. A filtering apparatus comprising a, casing containing filtering elements 'and a pump operable to force liquid through said elements, said pump having a reciprocable shaft with a transverse handle at the top portion; extensible means on said handle having downturned end portions; a flexible effluent conduit at the top of said casing adapted to be coiled about said top when not in use, said downturned end portions of said extensible means being operable to retain said conduit in said coiled condition.

2. A filter unit comprising a base having a tubular extension forming a pump cylinder; a. cylindrical casing seated on said base and surrounding said extension; a lower head member seated on the top of said casing; an upper head member seated on said lower head member and engaging said extension; a gland nut having threaded engagelnent with the top of said extension and operable to compress said head elements and said casing against said base; filter elements within said casing and flxedly attached to said lower head element; said base being provided with valve means admitting fluid to said pump cylinder and from said pump cylinder to the interior of said casing, said head elements being provided with an outlet permitting the discharge from said casing of fluid which has passed through said filter elements; and a reciprocable pump shaft within said cylinder and having an exterior handle.

3. The apparatus described in claim 2 wherein said handle has means operable to engage said gland nut when said shaft is at the bottom of its stroke, to tighten or loosen said gland nut on said pump cylinder.

4. Theapparatus described in claim 2 wherein said outlet means comprises a flexible conduit adapted to be coiled on the top of said upper head member and said handle has downturned portions operable to retain said coiled conduit ln place when said apparatus is not in use and said pump shaft is at the bottom of its stroke.

5. In the apparatus described in claim 2, a preillter unit having its outlet connected to said valve means, said valve being of the plug type; an annular tapered flange on the side of said valve, a removable retainer pin having a pair of legs passing through said base and resiliently pressing against said tapered ange to retain said valve in its seat; and a. handle operable to rotate 4 said valve, said handle having leg portions sliding in passageways in said valve whereby it may be pushed out of the Way into the body of said valve.

,6. A liquid purifying apparatus comprising a substantially cylindrical casing; a base closing the bottom of said casing and having a fluid inlet: means in said casing forming a pump cylinder extending vertically from said base; a passage in said base having a checkvalve therein, connectinlet; a reciprocable piston in said cylinder: a second passage in said base forming a fluidi outlet connecting the lower end of said cylinder with the interior of said casing; a head member-closing the top of said casing, said piston having a piston rod projecting through said head member; at least one annular series of vertical ceramic filtering tubes4v attached at their upper ends to said head'member, the lower ends of said tubes being closed; a discharge passageway in said head member communicating with the interior of said tubes at their upper ends.

7. The device described in claim 6 wherein said hollow filtering tubes are filled with silvered activated carbon.

,'8. A liquid purifying apparatus comprising a pre-filter having an inlet and an outlet; a main iilter having an inlet and outlet; a pump cylinder extending centrally of said main filter unit and having an inlet and outlet with check .valves therein; a piston reciprocable in said cylinder and operable through a suction and a pressure stroke; and a common reversible valve means including a stationary element and a reversibly movable element the latter of which is provided with cylinder inlet and outlet passages having check valvestherein, a port in said stationary element in communication with the prefllter outlet and normally registering with said cylinder inlet passage, and with said cylinder outlet passage When said movable element is reversed, a second port in said stationary element in communication with the main filter inlet and normally registering with said cylinder outlet passage, and with said cylinder inlet passage when said movable element is reversed.

9. A liquid purifying apparatus comprising a prelter unit and a main filter unit: a pump cylinder mounted within and extending centrally of said main lter unit and having an inlet and an outlet; a reciprocable piston in said cylinder. said piston 4having a suction and a pressure stroke; a base on said main filter unit having a first passageway connected to the discharge of vsaid prelter unit and a second passageway connected to the inlet of said main filter unit; a rotatable valve in said base having first and second conduits which when the valve is in one position are connected at one end to the inlet of said cylinder and at their other ends to said first and second passageways respectively, and when the valve is in l0 f within said cylinder and having an exterior handle.

11.*In a'liquid purifying apparatus: a closed casing having a fluid inlet and outlet, a pump within said casing, means for operating said 'pump projectingthrough a wall of said casing;

said pump having an inlet conduit connected to said fluid inlet and an outlet conduit discharging the fluid into the space between said pump and the inside walls of said casing in response toY operation of said operating means; a plurality of filtering tubes bodily spaced from said pump, disposed in said space between the pump and the inside wall of said casing and having their outer surfaces exposed to the liquid in said space, the bores of said tubes being closed at one end and connected at the other end to said fluid outlet, thus providing a compact arrangement with a maximum amount of filtering wall area in said space.

12. The combination defined by claim 11 -wherein said pump comprises a cylinder and said operating means comprises a piston rod reciprocable therein.

13. In a liquid purifying apparatus: a closed casing having a fluid inlet and outlet.. a pump within said casing. means for operating said pump projecting through a wall 'of said casing: said pump having means associated therewith for reanother position are connected to said second and rst passageways respectively; and check valve means in said conduits arranged to prevent the flow of uid from said cylinder through said rst conduits and to prevent the ilow of fluid from said main filter to said cylinder.

10. A lter unit comprising a base, a central tubular extention on said base to form a pump cylinder; a cylindrical casing attached to said base and surrounding said extension; a lower head member seated on the top of said casing; an upper head member attached to said lower head member: a gland nut having threaded engagement with the top of said extension and operable to compress said head elements against the top of said casing; filter elements within said casing and means attaching them to said lower head element; valve means operable to admit fluid through said base to said pump cylinder and from said pump cylinder to the interior of said casing, said head elements being provided with an outlet permitting the discharge from said.

casing of fluid which has passed through said lter elements; and a reciprocable pump shaft ceiving liquid from said inlet and discharging same into the space between said pump and the inside walls of said casing in response to said operating means, a plurality of filtering tubes disposed within said space, the outer surfaces of said filtering tubes being exposed to the liquid in said casing and their bores being in communication with said outlet.

14. In a liquid purifying apparatus, a casing having a base member with an inlet conduit therein, a head member with an outlet conduit therein and a peripheral wall, said members being separable from said wall, a plurality of hollow filtering elements within said casing held between said members having their hollows communicating with said outlet conduit, a pump operable to force liquid from said inlet conduit through the walls of said elements into said hollows and out through said outlet conduit, said pump having a cylinder in said casing secured to said base member, and extending through said head member, said pump having an inlet connected to said inlet conduit and an outlet connected to the inside. of said casing, a gland nut having threaded engagement with the top of said cylinder and operable to compress said members against the ends of said peripheral wall to make said casing uid tight and to facilitate. assembling and dismantling of said apparatus.

15. In a liquid purifying apparatus of the type defined in claim 14, a plunger in said pump cylinderhaving a rod `extending on the outside of said head member, an operating handle on said rod, and means on the underside of said handle for cooperation with said gland nut when the plunger is pushed in, to turn said nut.

16. In an apparatusas defined in claim 15, a prelter element for use in connection with said apparatus'having means for connection to said inlet conduit to supply the pump with preflltered fluid,` said element having attachment means for fixing it 'to the'base member of said casing for ease in carrying the complete filtering unit.

1'7. In a filtering unit as defined in claim 16, inlet and outlet connections for said pump cylinder with check valves therein normally communieating with said inlet conduit and said casing outside said hollow elements respectively, a reversible valve means in said base member for re versing the inlet and outlet connections to said pump cylinder to reverse the direction of flow of fluid through said unit for lushing said filtering elements when said valve means is reversed.

18. In a device having a reciprocally operated rod. an operating handle therefor and a bearing sleeve for said rod, a gland nut on the end of said bearing sleeve having means cooperating with interfitting means on the under side of said handle for turning said nut with said handle whenssaid rod has been pushed inwardly.

DAVID H. QUINN.

REFERENCES crrnn The following references are of record in the file of this patent:

Number Number 12 UNITED STATES PATENTS Name Date Chevallot Dec. 11, 1883 Miller Dec. 18, 1883 Manwaring et al. July 14, 1891 Nordtmeyer July 25, 1899 Nordtmeyer Sept. 24, 1901 Case et al May 26, 1908 Jarvis July 12, 1910 Duke et al Apr. 28, 1925 Knight Nov;;23, 1926 Imho et al June 20, 1933 Harlan et al Apr. 4, 1939 FOREIGN PATENTS Country Date Great Britain Mar. 20, 1899 Great Britain Mar. 21, 1907 Great Britain Mar. 31, 1905 Switzerland Dec. 1, 1938 

